JPH08195168A - Electron gun assembling device - Google Patents

Abstract

PURPOSE: To provide an electron gun assembling device capable of stably assembling electron guns having desired accuracy and emitting multiple beams arranged in a line. CONSTITUTION: Multiple stepped pillar-like center rods 12 are erected in a line on a base 11, and multiple electrodes G1 -G4 are coupled with the center rods respectively to assemble electron guns. In this electron gun assembling device, a through hole bored in the arrangement direction of the center rods 12 perpendicularly to the center axis of the center rods 12 is formed on at least one of the center rods 12, a rotation regulating rod 31 is inserted into the through hole, and the rotation drift of the electrodes coupled at the through hole forming portions of the center rods 12 is regulated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for assembling an electron gun for a cathode ray tube, and more particularly to an electron effective for assembling a multi-stage focusing electron gun for a color picture tube which emits three electron beams arranged in a row passing through the same plane. The present invention relates to a gun assembly device.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 5, a color picture tube has a funnel 3 in which a phosphor screen 2 composed of a phosphor layer of three colors formed on the inner surface of a panel 1 is integrally joined to the panel 1. The three-electron beam 6 emitted from the electron gun 5 sealed in the neck 4 is scanned through the shadow mask 7 to display a color image. In such a color picture tube, an in-line type color picture tube in which the electron gun 5 is an electron gun that emits three electron beams 6 arranged in a line passing through the same horizontal plane is currently the mainstream of the color picture tube.

This in-line color picture tube electron gun 5
An example is shown in FIGS. 6 (a) and 6 (b). These electron guns 5 are bipotential type multi-stage focusing electron guns,
The electron gun 7 shown in FIG. 6 (a) includes three cathodes K arranged in a row in the horizontal direction, three heaters (not shown) for heating the cathodes K, and phosphors for the cathodes K. The screen has first to fourth electrodes G1 to G4 sequentially arranged at predetermined intervals, and the heater, the cathode K, and the first to fourth electrodes G1 to G4 are integrally supported by a pair of glass columns 9. Is formed into a structure. Also, the electron gun 5 shown in FIG. 6B has three cathodes K similarly arranged in a row in the horizontal direction, and three heaters (not shown) for heating the cathodes K separately. Further, the first to sixth electrodes G1 to G6 are sequentially arranged at a predetermined interval on the phosphor screen side of the cathode K, and the heater, the cathode K, and the first to sixth electrodes G1 to G6 are formed by a pair of glass columns 9. It is formed in a structure that is integrally supported.

The respective electrodes of these electron guns 5 in the electron gun 5 shown in FIG. 6A are composed of plate electrodes of an integrated structure, and the first and second electrodes G1 and G2 are formed on the plate surface. Corresponding to the three cathodes K, three relatively small electron beam passage holes are formed. The third electrode G3 is composed of a cylindrical electrode having an integrated structure, and the surface thereof on the second electrode G2 side has three holes larger than the electron beam passage holes of the second electrode G2 corresponding to the three cathodes K. Individual electron beam passage holes are formed.
Further, on the surface of the third electrode G3 on the side of the fourth electrode G4, three larger electron beam passage holes are formed corresponding to the three cathodes K. The fourth electrode G4 is composed of a cup-shaped electrode having an integrated structure, and the surface of the fourth electrode G4 on the side of the third electrode G3 corresponds to the three cathodes K and the fourth electrode of the third electrode G3.
Three electron beam passage holes having the same size as the electron beam passage holes on the electrode G4 side are formed.

Regarding the electron gun 5 shown in FIG. 6 (b), the first, second and third electrodes G1, G2, G3 are the same as those of the electron gun 7 shown in FIG. 6 (a). , The fourth electrode G
Reference numeral 4 denotes a plate-shaped electrode having an integrated structure, and on the plate surface thereof, four cathodes G4 of the third electrode G3 are provided corresponding to the three cathodes K.
Three electron beam passage holes having the same size as the side electron beam passage holes are formed. The fifth electrode G5 is composed of a cylindrical electrode having an integrated structure. The surface of the fifth electrode G5 on the side of the fourth electrode G4 and the sixth electrode G6 corresponds to the three cathodes K and the electron beam on the side of the fourth electrode G4. Three electron beam passage holes having the same size as the passage holes are formed. The sixth electrode G6 is composed of an integrated cup-shaped electrode, and three electron beam passage holes of the same size as the electron beam passage holes of the fifth electrode G5 are formed on the surface of the fifth electrode G5 side. Has been done.

Moreover, in these electron guns 5, the center beam passage hole at the center is formed by the first electrode G1 to the fourth electrode G.
4 or the first electrode G1 to the sixth electrode G6 are coaxial with each other, but the pair of side beam passage holes on both sides are provided with the first electrode G1.
To the third electrode G3, and further the fifth and sixth electrodes G5, G
Although 6 is coaxial, the side beam passage hole of the fourth electrode G4 is located outside the side beam passage hole of the third electrode G3 in the arrangement direction of the three electron beam passage holes (away from the center beam passage hole). Eccentric).

With such an electrode structure, the electron gun 5 is
In the above, the electron beam generator is formed by the cathode K and the first to third electrodes G1 to G3 which are sequentially adjacent to the cathode K, and the third and fourth electrodes G3 and G4 or the third, fourth, fifth, and fifth electrodes are formed. A main lens portion is formed by the six electrodes G3, G4, G5 and G6. Then, the electron beam obtained from the electron beam generator is focused on the phosphor screen by the main lens portion and, at the same time, is concentrated on the phosphor screen due to the eccentricity of the pair of side beam passage holes of the fourth electrode G4.

Conventionally, such an electron gun 5 is shown in FIG.
As for the electron gun 5 shown in FIG. 7A, as shown in FIG. 7, a base 11 and three linear stepped columnar center rods 12 standing upright in a line on the base 11 are provided. Each of the center rods 1 is engaged with a pair of guide columns 13 provided upright on the base 11.
A plurality of spacers inserted between the first to fourth electrodes G1 to G4 fitted to 2 and a pressing portion 14 for pressing the cathode holding portion KH and the electrodes G1 to G4 fitted to the center rod 12. It is assembled using an electron gun assembling apparatus including 15a to 15d. Each of the center rods 12 is erected with the large-diameter portion side being the base 11 side.

In assembling the electron gun by this electron gun assembling apparatus, the electrodes having a large electron beam passage hole in each center rod 12 are arranged from the fourth, third, second and first electrodes G4, G3, G2, G.
The first to fourth electrodes G1 to G4 having an integral structure are fitted in the order of 1, and the spacers 15b to 15g are provided between the electrodes G1 to G4.
15d, and a spacer 1 on the first electrode G1 thereof.
The cathode holding portion KH is disposed via the 5a, and the cathode holding portion KH and the first to fourth electrodes G1 to G4 are pressed by the pressing portion 14 and embedded in a pair of heat-softened glass columns for assembly. To be

[0010]

As described above, as an electron gun for an in-line type color picture tube which emits three electron beams arranged in a row passing through the same horizontal plane, three cathodes arranged in a row and fluorescent light emitted from these cathodes are used. 3 which is obtained from an electron beam generator having a plurality of electrodes of a unitary structure which are sequentially arranged adjacent to each other on the body screen side and which is formed by a cathode and first, second and third electrodes which are sequentially adjacent to the cathode. The electron beam is focused on the phosphor screen by the main lens portion formed on the side of the phosphor screen, and at the same time, a pair of side beam passage holes of one electrode forming the main lens portion are connected to a pair of side electrodes of the other electrode. In some cases, the three electron beams are concentrated by eccentric to the side beam passage holes outside the arrangement direction of the three electron beam passage holes.

Conventionally, such an electron gun has a base, three linear stepped pillar-shaped center rods standing upright in a line on the base, and a pair of standing uprights on the base. An electron provided with a plurality of spacers that are inserted between the pressurizing portion that engages with the guide pillar and pressurizes the plurality of electrodes fitted to each center rod and the cathode holding portion and each electrode that fits into the center rod. It is assembled using a gun assembly device. For the assembly, for example, in an electron gun having four electrodes (first to fourth electrodes),
While fitting a plurality of integrated electrodes to each center rod,
A spacer is inserted between each electrode, and a cathode holding portion is arranged on the first electrode via the spacer, and the cathode holding portion and the first to fourth electrodes are pressed by a pressing portion to be softened by heating. It is assembled by being embedded in a pair of glass columns.

However, as described above, an electron gun in which a pair of side beam passage holes of some electrodes are eccentric with respect to a pair of side beam passage holes of another electrode is fitted to a linear stepped columnar center rod. When assembled, there is a problem in that the assembly accuracy of the electron gun deteriorates and the focusing performance of the color picture tube deteriorates.

That is, it has four electrodes as described above,
For an electron gun assembling apparatus in which the pair of side beam passage holes of the fourth electrode are eccentric with respect to the pair of side beam passage holes of the other electrode, the pair of side beam passage holes of the fourth electrode are fitted. The outer shape of the center rod of the portion is the diameter φ3 of the pair of side beam passage holes 17 of the third electrode G3 shown in FIG.
Accuracy Δφ 3, accuracy of the diameter φ 4 of the pair of side beam passage holes 18 of the fourth electrode G 4, Δφ 4, third and fourth electrodes G 3,
Accuracy of gap Sg3, Sg4 between center beam passage hole 19 (coaxial) of G4 and side beam passage holes 17 and 18, Sg3,
It is determined in consideration of ΔSg4 and the amount of axial deviation Sg4-Sg3.

For example, in a general electron gun of a 15-inch 90-degree deflection color picture tube, φ3 = φ4 = 5.5 mm Sg3 = 6.6 mm Sg4 = 6.8 mm Sg4-Sg3 = 0.2 mm and Δφ3 = ± 0.01 mm Δφ4 = ± 0.01 mm ΔSg3 = ± 0.01 mm ΔSg4 = ± 0.01 mm.

Therefore, Δφ3, Δφ4, ΔSg3, ΔS
Even when g4 is the minimum (-0.01 mm), the outer diameter of the center rod 12 in the portion where the pair of side beam passage holes 18 of the fourth electrode fit is 5.5- (0.01 ² +0. 01 ² ) ^1/2 mm = 5.48
It will be 5 mm.

By setting the outer diameter of the center rod 12 in the portion where the pair of side beam passage holes 18 of the fourth electrode fit in this way, the pair of side beam passage holes 1 of the third and fourth electrodes 1 is formed.
When the hole diameters of 7 and 18 are the minimum, that is, 5.5 mm-0.01 mm = 5.49 mm, as shown in FIG. 9, the pair of side beam passage holes 17 and 18 of the third and fourth electrodes are formed. Is relatively rotated around the center rod 12 into which the center beam passage hole 19 is fitted, the maximum inclination of these electrodes is tan ⁻¹ (5.49-5.485) × 2/6. 6 = 0.0
Although it is as small as 868 °, tan ⁻¹ (5. 5) when the pair of side beam passage holes 17 and 18 of the third and fourth electrodes have the largest hole diameter, that is, 5.5 mm + 0.01 mm = 5.51 mm. 51-5.485) × 2 / 6.6 = 0.4
This is about 5 times as large as 34 °, which is a major cause of rotational deviation of the beam spot on the phosphor screen.

For example, in a 15-inch 90-degree deflection color picture tube, when Sg3 = 6.6 mm and Sg4 = 6.8 mm, the distance between the pair of side beams on the phosphor screen is about 2 mm because of insufficient concentration. , While the eccentricity of only 0.2 mm of the pair of side beam passage holes of the fourth electrode reaches the phosphor screen, it changes to 6.6-2.0 / 2 mm = 5.6 mm. Therefore, when the maximum diameter of the pair of side beam passage holes of the one electrode forming the main lens portion, for example, the third electrode is 5.5 mm + 0.01 mm = 5.51 mm, the pair of side beams on the phosphor screen are The vertical interval y between the beam spots of the beam is (6.6-1.0): 0.2 = y: (5.51-5.4).
From 85) × 2, y = 1.4 mm. If this occurs in both the third and fourth electrodes that form the main lens portion, it will be approximately twice as large as 2.8 mm.

As described above, the vertical distance y between the beam spots of the pair of side beams on the phosphor screen.
Becomes larger and the array axis of the beam spots of the three electron beams is tilted obliquely with respect to the horizontal axis, the beam spots are adjusted so that they are concentrated at one point by the 4-pole magnet mounted outside the neck of the funnel. Then, as shown in FIG. 10, the perfectly circular beam spot 21 receives a force in the direction of the arrow by the magnetic field of the quadrupole magnet, and the elliptical distortion as shown by the broken line deteriorates the focusing performance of the color picture tube.

The present invention has been made to solve such a problem, and is not affected by the hole diameter accuracy of the electron beam passage holes of the electrodes constituting the electron gun for emitting a plurality of beams arranged in a row. An object of the present invention is to configure an electron gun assembly apparatus that can stably assemble an electron gun with desired accuracy.

[0020]

An electron gun assembling apparatus for assembling an electron gun by vertically arranging a plurality of stepped columnar center rods in a row on a base and fitting a plurality of electrodes to each of the center rods. In at least one of the center rods, a through hole that is orthogonal to the center axis of the center rod and penetrates in the direction of arrangement of the plurality of center rods is formed. It was formed in a structure that regulates the rotational displacement of the electrode that fits in the portion where the through hole is formed.

[0021]

As described above, at least one of the center rods is formed with a through hole which is orthogonal to the center axis of the center rod and penetrates in the direction of arrangement of the plurality of center rods, and the rotation regulating rod is fitted into the through hole. By forming a structure that regulates the rotation deviation of the electrode that fits in the through hole formation part of the center rod, even if there is a large variation in the hole diameter accuracy of the electron beam passage hole of the electrode, the beam of multiple beams on the phosphor screen The inclination of the array axis of the spots can be reduced, and the deterioration of the focusing performance of the cathode ray tube can be reduced.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

FIG. 1 shows an electron gun assembling apparatus for an in-line type color picture tube which is an embodiment of the present invention. The electron gun to be assembled has three cathodes arranged in a row and the first to fourth electrodes having an integral structure shown in FIG. 7A, and each electrode has a row arranged corresponding to the three cathodes. Electrons in which three electron beam passage holes are formed, and the pair of side beam passage holes of the fourth electrode are eccentric to the pair of side beam passage holes of the third electrode outside the arrangement direction of the electron beam passage holes. It's a gun.

This electron gun assembling apparatus has a base 11 and three center rods 12 vertically arranged on the base 11 in a line.
The first to fourth electrodes G1 fitted to the center rods 12 are engaged with a pair of guide columns 13 standing on the base 11 with the three center rods 12 sandwiched in the arrangement direction. .About.G4 and a pressing portion 14 for pressing the cathode holding portion KH and the like, and a plurality of spacers 15a to 15d interposed between the electrodes G1 to G4 fitted to the center rod 12.

As shown in FIG. 2, each center rod 12 has
It is formed in a linear stepped columnar shape, and the outer diameter of each part thereof is formed to a size into which the electron beam passage holes of the first to fourth electrodes of the electron gun are fitted, and the large diameter part side is the base. It is erected as a side. Moreover, in the electron gun assembling apparatus of this example, a rectangular shape that penetrates in the arrangement direction of the three center rods 12 orthogonal to the center axis of the center rods 12 at the portion where the third electrode of each center rod 12 is fitted. Through holes 30 are formed. Then, in each of the through holes 30 of these three center rods 12, the rotational displacement of the third electrode fitted to each of the center rods 12 is restricted.
The rectangular rotation restricting rod 31 shown in FIG.

As shown in FIG.
As shown in, the cup electrode G3T on the fourth electrode side of the third electrode
Has three electron beam passage holes 32a, 32b, 32c.
A rectangular through hole 33 into which the rotation restricting rod is fitted is provided on the side surface in the arrangement direction corresponding to the through holes of the respective center rods.

Assembling of the electron gun by this electron gun assembling apparatus is performed on the three center rods 12 erected on the base 11 by the fourth,
The third, second and first electrodes G4, G3, G2, G1 and the electrodes having a large electron beam passage hole are integrated into the first to the fourth structure.
The electrodes G1 to G4 are fitted together and each electrode G1 to G4
Spacers 15b to 15d are provided between the third electrode G3 and the third electrode G3. The third electrode G3 has a through hole provided on the side surface of the cup electrode G3T on the fourth electrode side in the arrangement direction of the electron beam passage holes and each center rod 12. The rotation regulating rod 31 is fitted and inserted into the through hole. Further, the cathode holding portion KH is arranged on the first electrode G1, and the cathode holding portion KH and the first to fourth electrodes G1 to G4 are pressed by the pressing portion 14. After that, the cathode holding portion KH and the planting portions provided on the first to fourth electrodes G1 to G4 are embedded in a pair of heat-softened glass columns for assembly.

When the electron gun assembly apparatus is constructed as described above, the rotation restricting rod 31 suppresses the rotational displacement of the third electrode G3 forming the main lens portion, thereby significantly improving the deterioration of the focusing performance. be able to.

That is, since the through hole 30 and the rotation restricting rod 31 of each center rod 12 in the electron gun assembly apparatus can be formed with a precision of 0.002 to 0.003 mm by machining, they are formed by pressing. It is smaller than the precision (± 0.01 mm) of the electrodes used, and its dimensional error can be ignored. Therefore, in the electron gun assembled by this electron gun assembling apparatus, the rotation deviation of the side beam passage hole around the center rod 12 fitted in the center beam passage hole of the third electrode G3 is caused by the fourth electrode of the third electrode G3. The dimension of the electron beam passage holes of the cup electrode G3T on the side is 2 in the arrangement direction.
Since it is 1.0 mm, tan ⁻¹ (0.01 × 2 / 21.0) = 0.0546 °.

Therefore, the through hole 30 and the rotation regulating rod 31 of each center rod 12 for regulating the rotation deviation of the side beam passage hole of the third electrode G3 as described above, together with the third electrode G3, form a main lens portion. If it is also provided for the electrode G4, it is (0.0546 × 2 / 0.434) × 100 = 25.1 when compared with the rotation deviation in the electron gun assembled by the conventional electron gun assembling apparatus (see FIG. 7).
%, And the vertical distance y between the beam spots of the pair of side beams on the phosphor screen can be reduced to y = 1.4 × 0.251 mm = 0.35 mm. Further, even when the rotational displacement of only one of the third and fourth electrodes G3 and G4 forming the main lens portion is restricted, [(1.4 + 0.35 / 2) /2.8] × 100 = 5
This is 6.3%, which is 1.575 mm, which is about 1/2 of the conventional 2.8 mm.

That is, as described above, the 3 of the electron gun assembling apparatus is used.
Through holes 30 are formed in each center rod 12, and each through hole 3 is formed.
The rotation restricting rod 31 is inserted into 0 to restrict the rotational displacement of one of the third and fourth electrodes G3 and G4 forming the main lens, so that the pair of sides on the phosphor screen are The rotation deviation of the beam, that is, the inclination of the array axis of the beam spots of the three electron beams on the phosphor screen can be improved by 100% -56.3% = 43.7%, and the rotation deviation of both electrodes is regulated. By doing so, it can be significantly improved to 100% -25.1% = 74.9%.

In the above embodiment, the through holes are formed in all the three center rods, and the rotation restricting rods are inserted into the respective through holes. Even if at least one through hole is formed and the rotation restricting rod is fitted and inserted into the through hole, an electron gun assembling apparatus having the same effect can be obtained.

Further, in the above embodiment, the electron gun of the in-line type color picture tube having the first to fourth electrodes of the integral structure has been described, but the present invention is the same as that of the integral structure shown in FIG. 6 (b). The same effect can be obtained by applying the present invention to other electron guns such as a unipotential multistage focusing electron gun as well as a bipotential multistage focusing electron gun having first to sixth electrodes.

[0034]

EFFECTS OF THE INVENTION In an electron gun assembling apparatus for assembling an electron gun by arranging a plurality of stepped columnar center rods upright in a row on a base and fitting a plurality of electrodes to each of these center rods, A through-hole is formed in at least one of the rods, the through-hole being orthogonal to the central axis of the central rod and penetrating in the direction in which the central rods are arranged. By forming the structure that regulates the rotation deviation of the electrodes, even if the hole diameter precision of the electron beam passage holes of the electrodes is large, the inclination of the array axis of the beam spots of the multiple beams on the phosphor screen can be made small, and the cathode ray tube It is possible to reduce the deterioration of the focus performance of.

[Brief description of drawings]

FIG. 1 (a) is a front view showing the configuration of an electron gun assembly apparatus for an in-line type color picture tube which is an embodiment of the present invention, and FIG. 1 (b) is a side view thereof.

FIG. 2 (a) is a front view showing the configuration of a center rod of the electron gun assembly apparatus, and FIG. 2 (b) is a sectional view thereof.

FIG. 3 (a) is a front view showing the structure of a rotation restricting rod of the electron gun assembly apparatus, and FIG. 3 (b) is a sectional view thereof.

FIG. 4 (a) is a plan view showing the structure of a cup electrode on the side of the fourth electrode of the third electrode forming the main lens portion, FIG.
4B is a front view with a partial cross section, and FIG. 4C is a side view with a partial cross section.

FIG. 5 is a diagram showing a configuration of a color picture tube.

6 (a) and 6 (b) are diagrams showing the configurations of electron guns having different color picture tubes.

7 is a diagram showing a configuration of a conventional electron gun assembling apparatus for assembling the electron gun shown in FIG. 6 (a).

FIG. 8 is a diagram for explaining the relationship between the center rod and the third and fourth electrodes of the conventional electron gun assembly apparatus.

FIG. 9 is a diagram for explaining a problem of the conventional electron gun assembly apparatus.

FIG. 10 is a diagram for explaining the deterioration of focus performance that occurs when the array axis of the beam spots of the three electron beams is tilted with respect to the horizontal axis on the phosphor screen.

[Explanation of symbols]

 11 ... Base 12 ... Center rod 14 ... Pressurizing parts 15a to 15d ... Spacer 30 ... Through hole 31 ... Rotation regulating rods 32a, 32b, 32c ... Electron beam passage hole 33 ... Through hole G1 ... First electrode G2 ... Second Electrode G3 ... Third electrode G4 ... Fourth electrode KH ... Cathode holder

Claims (1)

[Claims] 1. An electron gun assembling apparatus for assembling an electron gun, wherein a plurality of stepped pillar-shaped center rods are erected in a row on a base, and a plurality of electrodes are fitted to each of these center rods. A through hole is formed in at least one of the center rods and is orthogonal to the center axis of the center rod and penetrates in the arrangement direction of the plurality of center rods. The rotation regulating rod is fitted into the through hole to form the through hole forming portion. An electron gun assembling apparatus, which is formed in a structure that regulates a rotational displacement of an electrode fitted to the.